Blackwing - Kalut the Moon Shadow (German) - "Schwarzflugel - Kalut der Mondschatten" (AC11-DE005) - Advent Calendar 2011 (Adventskalender) Limited

By sending this card from your hand to the Graveyard during the Damage Step when 1 face-up Blackwing monster you control battles, that monster gains 1400 ATK until the End Phase of that turn.